Braking member



m 29, 1934. L SMITH 1,960,352

BRAKING MEMBER Filed Feb. 5, 1931'.

awzzzzzm 3nnentor G eoz e .Z. Um iih Gttomeg Patented May 29, 1934 ATNT orris United States Urdnance Company, Washington, D. 0., a corporation of Virginia Application February 5,

7 Claims.

The object of my invention is to provide a braking member for internal brakes which Will embody the full wrap method of self-energization and at the same time maintain its shape as the brake lining wears down so that its adjustment may be made automatic.

My type of braking member is particularly adapted for use in connection with the general type of braking mechanism described and claimed in my copending application 362,534, filed May 13, 1929 and has certain practical advantages over the braking member shown in my aforesaid prior application.

In the drawing chosen to illustrate my invention,

Figure 1 is a side elevation of the brake band complete;

Figure 2, a section on line 22 of Figure 1;

Figure 3, a section on line 3-3 of Figure 1; and

igure 1, a section on line 4% of Figure 1.

The numeral represents the brake band which is rolled up from one continuous strip of steel. This band is stiiiened in three sections by the webs 11 and 12 welded to it and by the channel section 13 shown more plainly in Figure 4. The pad 14 is secured to the band to act as a stop for the adjusting screw 15 of the slack adjuster A. The arm 16 is secured to the web 11 and terminates in a pivot bearing 17 to which the brake lever 18 pivots. The pad 19 is also secured to the web 11 and to the band 10 and acts as an anchor clip making contact with the anchor post 20. To prevent the band from getting out of round I employ a special construction at the junction of the stiffened sections as follows. At the point B I bring the webs 11 and 12 into contact along the line c-d. so that the band cannot be bent in at this point, but can be bent out. This reduces the danger of deforming the band when relining it. As the band expands into its drum it will flex at this point B, but to such a sli ht degree that I can weld the two webs 11 and 12 to the band up to their ends leaving no flexible section in a circumferential direction,

At the point E I extend the channel section 13 so that it overlaps the web 12 a small amount to reduce danger of bending the band out of shape at this point. Web 12 is welded to the band from point e to point 1. This leaves the extension fg of the web disconnected to permit J an expanding action while preventing any further contracting action.

To ensure a proper positioning of the two ends of the band the part 16 carrying pivot hole 17 is rigid with the end 21 of band while the end 22 1931, Serial No. 513,695

of band is held up by the release spring 23 against body 24 of slack adjuster A. This body being connected by pivot 25 to brake lever 18 it is evident that the end 22 will be held in a fixed position with respect to end 21, so that the braking surface on end 21 will be on the same circle as that on .22. With the band in place the abutment 26 limits the contracting movement of the band, and in this position the pivots 17 and 25 are so positioned that the band is a true circle. It will be noted that the line 72. through the centers of these pivots passes close to and to the right of the center o of the band. When the brake is applied by a ccunter-clockwise rotation of the lever 18 the pivot 25 moves to the right and this line through the centers of the pivots l7 and 25 thenswings to or even beyond the center of the brake as shown by the line is. This movement being so close to the dead center of the centers of the pivots l7 and 25 and the center 0 of the band there will be practically no radial movement of the center of pivot 25 and therefore no such movement of end 22 of the band with respect to end 21 of the band. With the band removed from the brake the gap between its ends would close a trifle until movement is arrested by the free end of the long arm of lever 18 hitting end 22 of the band, but under such conditions the radial movement between the band ends would be so small as to have no tendency to distort the band. Should the band he dropped after removal this support between the ends would prevent the band being bent out of shape if it should hit on or near one end. In this manner the band becomes selfsupporting and does not rely upon or require at any time any adjusters or supports-to hold its true circular shape. In other words the crossconnection between the ends of the band just described will hold the latter in its true circular shape irrespective of whether the band is incorporated in or removed from a brake mechanism.v

This cross connection between the ends of the band constitutes a continuation in part of my prior application 362,534. Also the brake lining is prevented from wearing down any faster on the end 21 than it will be on the end 22. This fixes the area of greatest wear of lining at a point near the middle of that part of band reinforced by the stiffening web 11.

I claim:

1. In a brake mechanism, an expanding brake member and two abutting reinforcements secured thereto limiting the contracting action of said member.

.2. In a brake mechanism, an expanding brake member and two stiffening webs secured thereto with their adjacent ends in abutment when said member is in a contracted position.

3 In a brake mechanism, an expanding brake member, one portion of said member having its edges turned in to form a channel section, and an adjacent portion of said member being-'stifiened by a web centrally located with respect to the flanges of said channel section, and overlapping said flanges in a circumferential direction.

4. In a brake mechanism, an expanding brake member with separable ends having a plurality of separate reinforcements, each extending longitudinally of the member, one of the end reinforcements being formed by inturned edges of the member and the remainder of said reinforcements by centrally disposed inwardly extending webs, the reinforcing web adjacent said inturned edges extending between the latter and the adjacent ends of the web reinforcements abutting each other when the brake member is contracted.

5. In a brake mechanism, an expanding brake member having terminal reinforcements and an intermediate reinforcement each extending longitudinally of the member, one of the terminal reinforcements being formed by inturned edges of the member and the remaining reinforcements by centrally disposed inwardly extending webs, one end of the intermediate reinforcement extending between said inturned edges and the other end thereof abutting the adjacent end of the other terminal reinforcing web when the brake member is contracted.

6. In a brake mechanism, an expanding brake member of circular form having separable ends, and means cross-connecting said ends, said means being entirely supported by the band and maintaining the ends of the latter at substantially equal distances from the center of the circular form defined by the brake member.

7. In a brake mechanism, an expanding brake member or circular form having separable ends, and means cross-connecting said ends both when the band is incorporated in or removed from said mechanism and at all times maintaining said ends at substantially equal distances from the center of the circular form defined by the brake member.

GEORGE L. SMITH. 

